in which 在英语解释中常常使用,起什么作用?

当你要精确表达"在...里面"时, 用in which来代替下列例句中表示"in which"的连词where; in which不能代替代词和不可数名词where.
where (Conjunction) Where作连词的含义比in which广泛,笼统.
The place in, at or to which.
He knows where he’s going.
The situation in which.
He’s exactly where he belongs. 可用in which来代替
where (Pronoun)
The place in which.
He lives within five miles of where he was born.
where (uncountable Noun)
The place in which something happens.
A good article will cover the who, the what, the when, the where, the why and the how.